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  1. #1
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    Mach 5.7 rear end feels loose?

    Trail ride yesterday ended with a couple miles of road back to the cars & experienced a very odd sensation that the rear of bike was like a noodle side to side. Thought I had a flat so pulled over...nope, rear tire was maybe 5 lbs softer than usual (running 2.35 Nevegal's).

    Rode a little more & same sensation when peddling hard. Felt like & could visually see the rear moving all over the place. Friend behind confirmed and we both pulled over to check bolt, look for cracks...nothing. Slow pedal back to the car.

    Today, I took the bike into shop, they pulled all the bolts, looked over bearings, & didn't find anything. Mechanic mentioned having the rear tire soft could have been the culprit, but I'm not totally convinced. I'm having them hold overnight & mechanic said he take for a spin down the road etc.

    Has anyone else experience anything like this? I was convinced yesterday that I had a cracked bolt or something going on, but now I'm puzzled as to why this felt like a wet noddle rear. Crazy...

  2. #2
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    Sounds like something is loose for sure. Have you checked the wheel itself yet? I've had a wheel lose tension before and it wobbles all over the place.
    Desert Sunset Calls/Upward, Pain, Perseverance/Welcome Solitude

  3. #3
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    Wet noodle is exactly how I would describe the feel of my 5.7 when the bearings in the DW link (lower link) failed. Make sure your mechanic has pulled the link and inspected the bearings. I had one bearing that was completely destroyed, and the rest were very notchy. When I mashed on the pedals it looked like the bottom bracket was moving side to side. I went through the same process you did, checking my wheels, tires, and for cracks in the frame. It was a very different sensation than a slightly low tire.

  4. #4
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    Dealer pulled it all yesterday when I was there...all bolts & links removed, but said it all looked good. He explained that there would be obvious play if apply side pressure if there was a failure & this wasn't the case when he was torquing on on while pushing on the tire/rim. I explained that this experience is only present while peddling forcefull (sprint or turning a larger gear).

    Spoke tension, rear wheel etc. all check out fine.

    Now I'm thinking I'm crazy since nothing was obvious. I'm going to call into dealer & ask if they've taken it for a spin & see what they say.

    Quote Originally Posted by emptyvoxel View Post
    Wet noodle is exactly how I would describe the feel of my 5.7 when the bearings in the DW link (lower link) failed. Make sure your mechanic has pulled the link and inspected the bearings. I had one bearing that was completely destroyed, and the rest were very notchy. When I mashed on the pedals it looked like the bottom bracket was moving side to side. I went through the same process you did, checking my wheels, tires, and for cracks in the frame. It was a very different sensation than a slightly low tire.

  5. #5
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    Interesting. I'm having the same thing happen to me but no amount of pulling, pushing, or levering results in any obvious looseness of the frame when I'm not riding it. As I peddle hard down paved roads and look down at the RT, it looks like it's shifting side to side. I need to get someone to follow me and check while I ride though.

    I do notice some lateral flex when I pull the top of the rear wheel while pushing on the seat. Maybe the wheels are flexing more than we're used to? I'm kinda thinking that the DW Link design is just new to me and I'm not used to how it rides in some situations.

  6. #6
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    Pivots are usually very stiff laterally. I experienced the same sensation recently on my 2013 Mach 429. As the poster above said it was my DW link bearings. Mine failed after only 3 months.
    My LBS told me that Pivot have reduced the number of bearings in the links and some of these are failing prematurely.
    If you stand to the side of the bike facing it and apply some pressure on the pedals you should see the movement. Get someone else to have a close look to work out where the movement is coming from.
    Mine was drive side DW link bearings.

  7. #7
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    Dealer replaced my entire lower link + bearings. Mechanic was not there when I picked up so didn't get a chance to ask specifics...seems good now. As I mentioned in my previous post, the rear end felt like a wet noddle & not just some slight noticed movement...very odd sensation that made me pull over. Awesome bike otherwise! Waiting for a team green 429C now...


    Quote Originally Posted by Hugor View Post
    Pivots are usually very stiff laterally. I experienced the same sensation recently on my 2013 Mach 429. As the poster above said it was my DW link bearings. Mine failed after only 3 months.
    My LBS told me that Pivot have reduced the number of bearings in the links and some of these are failing prematurely.
    If you stand to the side of the bike facing it and apply some pressure on the pedals you should see the movement. Get someone else to have a close look to work out where the movement is coming from.
    Mine was drive side DW link bearings.

  8. #8
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    Quote Originally Posted by emptyvoxel View Post
    Wet noodle is exactly how I would describe the feel of my 5.7 when the bearings in the DW link (lower link) failed. Make sure your mechanic has pulled the link and inspected the bearings. I had one bearing that was completely destroyed, and the rest were very notchy. When I mashed on the pedals it looked like the bottom bracket was moving side to side. I went through the same process you did, checking my wheels, tires, and for cracks in the frame. It was a very different sensation than a slightly low tire.

    This is exactly what happened to my 5.7c, when i put the bike on my work stand and tried moving the rear wheel side to side, I could see movement. Ended up one of the bearings failed in the lower blue link. when I took it apart, it was like the bearings were crushed up into small fragments. Pivot swapped out the blue link no charge and it has been good ever since.

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